Some electronic devices are configured to receive energy or power wirelessly. The user may place the electronic device on a charging surface of a wireless charging or transmitter device to transfer energy from the transmitter device to the electronic device. The transmitter device transfers energy to the electronic device through inductively coupling between a transmitter coil in the transmitter device and a receiver coil in the electronic device.
In some instances, a wireless transmitter device is constructed to only transfer energy to a particular receiver device. This can increase the cost to a user who uses wireless energy transfer for multiple electronic devices. Because each electronic device may operate only with a particular charging device, a user may be required to purchase multiple charging devices.